Ruptures, cracks, and holes often occur in underground conduits such as sanitary sewer lines, storm sewer pipes, and other gravity flow systems and service lines. Repairing these ruptured conduits, from within, is far less expensive and less dangerous than excavating and replacing the damaged sections. One such repair method is to introduce into the conduit a polyester-fiberglass or other structural composite liner impregnated with a thermosetting resin. The liner is wrapped around and secured to an inflatable bladder which is positioned at the rupture and inflated, forcing the repair liner against the inside wall of the conduit. The impregnated composite liner adheres to the damaged inner surface of the conduit and hardens. After completion of the curing process, the bladder is deflated and removed from the conduit. Known related art include U.S. Pat. Nos. 4,995,761 and 5,049,003 to Barton, U.S. Pat. No. 5,628,345 to Fisco, U.S. Pat. No. 5,322,653 to Muller, U.S. Pat. No. 3,202,562 to Lang, et al., U.S. Pat. No. 3,261,374 to Anderson, et al., U.S. Pat. No. 4,776,370 to Long, U.S. Pat. No. 4,880,035 to Vetter, U.S. Pat. No. 4,950,446 to Kinumoto, et al., U.S. Pat. Nos. 4,985,196 and 5,091,137 to LeDoux, et al., U.S. Pat. No. 5,199,463 to Lippiatt, U.S. Pat. No. 5,203,377 to Harrington, U.S. Pat. Nos. 5,213,727 and 5,346,658 to Gargiulo, U.S. Pat. No. 5,265,648 to Lyon, U.S. Pat. No. 5,501,248 to Kiest, et al., and U.S. Pat. No. 6,019,136 to Walsh, et al., the contents of U.S. Pat. No. 6,019,136 are incorporated by reference.
The methods and apparatus, for example, as described in the above cited patents provides for repairs of cracks or leaks in straight sections of pipes, but is less useful for curved sections of pipe, especially curves of 90 degrees or more due to the lack of conformity of the repair liner. Such a repair is often needed in the 90 degree curved section of pipe often found beneath a commode, especially when the commode is situated on a cement slab. Prior repairs often required excavating around the 90 degree section, removal of the damaged 90 degree section, replacement with a new 90 degree section and replacement of the concrete that was removed in the excavation.
What is needed is a system that will repair cracks or leaks in curved sections of pipes without gaining access to the outside surfaces of the pipes (e.g. excavation).